Walk into almost any stage business agency , and you ’ll probably find a photocopier ( " copier " ) with a communication channel of the great unwashed waiting to use it . For most businesses , modest or large , the copier has become stock equipment , much like have a desk to bring at and a death chair to sit in .
What if you had to resort to making C copies of important documents , as many people did before copiers came along ? Or worse , imagine how boring it would be if you had to recopy everything by helping hand ! Most of us do n’t think about what ’s conk on inside a copier while we wait for copies to shoot neatly out into the paper tray , but it ’s moderately amazing to think that , in mere seconds , you could produce an exact replica of what ’s on a piece of paper of paper ! In this clause , we will research what happens after you crusade " Start " on a photocopier .
The Basics
The man - end of have a copy begins with a few basic step :
What happen inside the copier at this compass point is awesome ! At its heart , a copier works because of one basic physical principle : polar charges pull in .
As a fry , you probably act as withstatic electricityand balloon . On a wry winter day , you may rub a balloon on your sweater and create enough static electrical energy in the balloon to create a noticeable forcefulness . For good example , a balloon charged with stable electrical energy will pull small bit of paper or particles of sugar very easy .
A copier uses a similar process .
There are three things about the barrel and the toner that lease a copier perform its thaumaturgy :
Thedrum , or belt , is made out ofphotoconductivematerial . Here are the actual steps need in making a photocopy :
When the copier illuminates the piece of paper of newspaper publisher on the glass Earth’s surface of a copier , a blueprint of the trope is see onto the positively charged photoreceptive drum below . Light shine from blank areas on the page hits the barrel and cause the charged particles coat the drum ’s aerofoil to be waste . This leaves positive bang only where there are dark areas on the paper that did not ruminate lighting . These positive accusation attract negatively charged toner . The toner is then transplant and coalesce to a positively charged sheet of paper .
Inside a Photocopier
If you take a photocopier aside , you might be whelm by how many dissimilar character there are . However , the actual photocopying process rely on only a few , key pieces :
In the follow sections , you ’ll acquire about each of these part .
Photoreceptor Drum
Thephotoreceptor drum(or , in some photocopier , belt ) is the heart of the system . A drum is basically a metal roller covered by a layer ofphotoconductivematerial . This bed is made out of asemiconductorsuch as selenium , germanium or silicon . What make element like selenium so cool is that they can impart electrical energy in some sheath , but not in others . In the dark , the photoconductive layer on the metal drum acts as an insulator , refuse the flow of negatron from oneatomto another . But when the layer is hit bylight , the energy of the photons liberates electrons and allows current to decease through ! These newly freed electrons are what neutralizes the positive commission coat the brake drum to mold the latent figure of speech .
It ’s easy to imagine how you might project a copy of an image on a photoreceptive belt that has roughly the same proportion as the sheet of paper containing the simulacrum . A problem emerges when you think about doing the same thing on a thin , cylindrical drumfish . How can the surface area of the drumfish possibly tally the literal the three estates on a sheet of paper ? The solution is to simply rotate the drum while you ’re making a transcript . If you revolve the drum in lockstep with the apparent motion of the light beam of light across the original document , you could construct the image strip by strip . After one strip of light is focused onto a corresponding swath of the barrel , the barrel rotates to expose a fresh area of the photoconductor . Meanwhile , the previously exposed region of the drum swings into middleman with the toner , and then with the paper .
Because the distance of a standard impress page is a lot larger than the perimeter of the drum in a modern photocopier , one full revolution of the drumfish will only replicate a little part of the Thomas Nelson Page . The drum really has to be cleaned , recharge with ion , exposed to photons , and patter with toner multiple time so as to duplicate the entire original . To the casual percipient , the process appears continuous , because it ’s all seamlessly coordinated inside the photocopier as the drum rotates .
Corona Wires
For a photocopier to work , a field of positive explosive charge must be generate on the surface of both the drum and the transcript paper . These chore are accomplished by thecorona wire . These wire are subjugate to a high voltage , which they subsequently transfer to the drum and composition in the form of electrostatic electricity .
One of these wires is stretched parallel to the tympan control surface and charges the photoconductive control surface with positive ion , and the other wire is positioned to surface the newspaper ’s surface as the paper shoots by on its way to the drum .
Lamp and Lenses
Making a photocopy require alight sourcewith enough energy to boot negatron out of the photoconductive speck . What wavelengths of light can do this ? It turns out that most of thevisible spectrumof light contains enough energy to drive the process , especially the fleeceable and blue end of the spectrum . Anything lower than the red portion of the seeable spectrum does n’t have enough gusto to activate the photoconductor . And , although ultraviolet luminousness has more than enough firepower to make a photocopy , it can be very detrimental to our eyes and skin . This is why photocopier utilise a plain oldincandescentorfluorescent bulbto flash Inner Light onto the original document .
When the lamp in the copier is turned on , it actuate across the interior of the copier , illuminating one strip of the paper at a sentence . A mirror attach to the lamp meeting place conduct reflect light through a crystalline lens onto the rotating drum below . The genus Lens works just like the one on your camera . It allows you to centre a copy of the picture in a specific place . Although you ca n’t really focus the picture on a photocopier to make the concluding product more or less blurry , you’re able to change the space between the lens of the eye and the original or between the crystalline lens and drum to eitherreduceormagnifythe size of it of the original paradigm on your copy .
Toner
Toner is sometimes bring up to asdry ink , but toner is n’t in reality ink at all ! Ink is a pigmented liquid . Toner is a o.k. , negatively charged , credit card - found powder . The dark colouration in photocopier toner comes from pigments blended into the plastic particles while they are being made .
In your photocopier , toner is stuck on expectant , positively charged beads and stored inside a toner pickup . When toner - coated drop are rolled over the drum , the toner particles find the positively charged ions on the unexposed areas on the drum ’s airfoil much more attractive than the weakly charged bead . The same molecule are subsequently even more drawn to the electrostatically charge up paper . The plastic in the toner lets you keep it from start ship once you ’ve finally got it on the newspaper ; all you have to do is apply heat to the toner , and the plastic particles melt and fuse the pigment to the theme .
The Fuser
The fuser provides the finishing touches that make the toner image on a rag of composition permanent . The fuser has to do two thing :
All that ’s required to fulfil these undertaking isquartz pipe lampsandTeflon - coated roll . The sheet of composition is send between two of the rollers . Then , the curler gently exhort down on the page to embed the toner in the newspaper fiber . Meanwhile , inside the roll , the lamp are on , generate enough warmth to dissolve the toner . Why does n’t the toner melt onto the hair curler instead ? Just like non - stick coating prevents your dinner from becoming glued to the bottom of your frying goat god , the Teflon coating the rollers keep the toner and composition from sticking to them .
Putting It All Together
In a photocopier , thelight - induced conductivityof the drum is exploited to make alatent imagein the form of electric charge on the surface of the drum . This image is made visible and transport to report using a special , charged toner . Here ’s how it all comes together to make a copy :
By the meter you reach for your copy in the assembling tray , the photocopier has already machinate for the next go - round by again cleaning off the drumfish ’s surface and enforce a fresh coat of positively charged ions to it .
For more data on photocopiers and related issue , check out the links on the next page .
